How do we access Vert, Norm and UV data then print to a text file using Blender/Python?
In order to export the triangles of the default scene's cube the process would be as follows.


Select the Cube, switch to Edit Mode
Select all faces
Load the Texture in UV-Image Editor 
UV-Unwrap U Smart UV-Project
Create a Material and Texture , assign the texture and UV-Map
Convert the quads to tris Ctrl-F Ctrl-T
Switch to Object Mode (Important)


Run the script:

import bpy

#bpy.ops.mesh.quads_convert_to_tris()

ob = bpy.context.object

with open("c:\\tmp\\{ob.name}.txt".format(ob=ob), "w") as file:
    file.write("GLfloat {ob.name}[] =\n{\n".format(ob=ob))

    for face in ob.data.polygons:
        for vert, loop in zip(face.vertices, face.loop_indices):
            coord = ob.data.vertices[vert].normal
            normal = ob.data.vertices[vert].co
            uv = ob.data.uv_layers.active.data[loop].uv
            file.write("\t{co.x}, {co.y}, {co.z}, {n.x}, {n.y}, {n.z}, {uv.x}, {uv.y},\n".format(co=coord, n=normal, uv=uv))

    file.write( "};\n")


Find the output file in the temp directory:

GLfloat Cube[] =  
{
    0.577349, 0.577349, -0.577349, 1.000000 1.000000 -1.000000, 0.666667, 0.333333,
    0.577349, -0.577349, -0.577349, 1.000000 -1.000000 -1.000000, 1.000000, 0.333333,
    -0.577349, -0.577349, -0.577349, -1.000000 -1.000000 -1.000000, 1.000000, 0.666667,
    0.577349, 0.577349, 0.577349, 1.000000 0.999999 1.000000, 0.333333, 0.666667,
    -0.577349, 0.577349, 0.577349, -1.000000 1.000000 1.000000, 0.333333, 0.333333,
    0.577349, -0.577349, 0.577349, 0.999999 -1.000001 1.000000, 0.666667, 0.666667,
    0.577349, 0.577349, -0.577349, 1.000000 1.000000 -1.000000, 0.333333, 0.333333,
    0.577349, 0.577349, 0.577349, 1.000000 0.999999 1.000000, 0.000000, 0.333333,
    0.577349, -0.577349, -0.577349, 1.000000 -1.000000 -1.000000, 0.333333, 0.000000,
    0.577349, -0.577349, -0.577349, 1.000000 -1.000000 -1.000000, 0.333333, 0.333333,
    0.577349, -0.577349, 0.577349, 0.999999 -1.000001 1.000000, 0.333333, 0.000000,
    -0.577349, -0.577349, -0.577349, -1.000000 -1.000000 -1.000000, 0.666667, 0.333333,
    -0.577349, -0.577349, -0.577349, -1.000000 -1.000000 -1.000000, 0.666667, 0.000000,
    -0.577349, -0.577349, 0.577349, -1.000000 -1.000000 1.000000, 1.000000, 0.000000,
    -0.577349, 0.577349, 0.577349, -1.000000 1.000000 1.000000, 1.000000, 0.333333,
    0.577349, 0.577349, 0.577349, 1.000000 0.999999 1.000000, 0.000000, 0.333333,
    0.577349, 0.577349, -0.577349, 1.000000 1.000000 -1.000000, 0.333333, 0.333333,
    -0.577349, 0.577349, 0.577349, -1.000000 1.000000 1.000000, 0.000000, 0.666667,
    -0.577349, 0.577349, -0.577349, -1.000000 1.000000 -1.000000, 0.666667, 0.666667,
    0.577349, 0.577349, -0.577349, 1.000000 1.000000 -1.000000, 0.666667, 0.333333,
    -0.577349, -0.577349, -0.577349, -1.000000 -1.000000 -1.000000, 1.000000, 0.666667,
    0.577349, 0.577349, 0.577349, 1.000000 0.999999 1.000000, 0.000000, 0.333333,
    0.577349, -0.577349, 0.577349, 0.999999 -1.000001 1.000000, 0.000000, 0.000000,
    0.577349, -0.577349, -0.577349, 1.000000 -1.000000 -1.000000, 0.333333, 0.000000,
    0.577349, 0.577349, -0.577349, 1.000000 1.000000 -1.000000, 0.333333, 0.333333,
    -0.577349, 0.577349, -0.577349, -1.000000 1.000000 -1.000000, 0.333333, 0.666667,
    -0.577349, 0.577349, 0.577349, -1.000000 1.000000 1.000000, 0.000000, 0.666667,
    -0.577349, 0.577349, 0.577349, -1.000000 1.000000 1.000000, 0.333333, 0.333333,
    -0.577349, -0.577349, 0.577349, -1.000000 -1.000000 1.000000, 0.666667, 0.333334,
    0.577349, -0.577349, 0.577349, 0.999999 -1.000001 1.000000, 0.666667, 0.666667,
    -0.577349, 0.577349, -0.577349, -1.000000 1.000000 -1.000000, 0.666667, 0.333333,
    -0.577349, -0.577349, -0.577349, -1.000000 -1.000000 -1.000000, 0.666667, 0.000000,
    -0.577349, 0.577349, 0.577349, -1.000000 1.000000 1.000000, 1.000000, 0.333333,
    0.577349, -0.577349, 0.577349, 0.999999 -1.000001 1.000000, 0.333333, 0.000000,
    -0.577349, -0.577349, 0.577349, -1.000000 -1.000000 1.000000, 0.666667, 0.000000,
    -0.577349, -0.577349, -0.577349, -1.000000 -1.000000 -1.000000, 0.666667, 0.333333,
};


The code is based on ideasman42 answer here: Exporting UV coordinates

.blend file as demo.